If I had a buck for every person I know who said "I want to learn how to brew my own beer," I'd probably be able to buy myself a brewery (see slide six). So get a beer enthusiast a homebrew kit. The best approach is to go to your local homebrew shop and buy it there, because the shop owner is probably also a homebrewer and will be able to give you good advice, including which equipment is absolutely necessary, and which style of beer is best for a first attempt. We got our five-gallon-capacity kit from the fine people of Brooklyn Homebrew. Another company, Brooklyn Beer Shop, sells one-gallon kits.
$50 to $300, Brooklyn Homebrew and Brooklyn Beer Shop